MST1 and neoplasm: These studies suggest that (1) MST1/2 does not always signal through LATS1/2 to YAP, (2) MST/LATS signalling are dispensable for YAP regulation in specific cell types, (3) MST1/2 signalling can function completely independent of the LATS/YAP signalling branch in specialised cell types, and (4) YAP does not always function as a proto-oncoprotein, but could also have context dependent tumour suppressive activity in the colon.